1. Field of the Invention
The present invention relates to error-resistant digital logic devices, and in particular to a system and method for correcting errors in a logic device.
2. Description of the Related Art
Computer memory and other semiconductor components are susceptible to environmental effects that can cause them to fail. One class of failures occurs as a result of exposure to radiation, which is common in the space environment. Such radiation can be devastating to a satellite lacking adequate safeguards. When cosmic radiation passes through a sensitive semiconductor component in a satellite, one of three possible conditions may result.
In a microprocessor or RAM chip, a single-event upset (SEU) can occur wherein the contents of a particular logical device such as a register or a divider become inverted (e.g. a bit flips from 0 to 1). As a result, sensor data can be corrupted, algorithms can fail, and the satellite firmware can be adversely affected. A corrupted program could attempt to execute random code or data in the memory may be lost.
Furthermore, different semiconductor devices have different susceptibilities to radiation induced failures. Some device designs may reduce (or virtually eliminate) the risk of a radiation induced failure, however, it is often not reasonable to apply such techniques to every semiconductor device. What is needed is a system and method for recovering from SEUs. The present invention satisfies that need.